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arXiv · 1901.03512

An unstable three dimensional KAM torus for the quintic NLS

Trung Nguyen
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Abstract

We consider the quintic nonlinear Schr{\"o}dinger on the circle. By applying a Birkhoff procedure and a KAM theorem, we exihibit a three dimension invariant torus that is linearly unstable. In comparison, we also prove that two dimensional tori are always linearly stable.

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Trung Nguyen. 2019-01-11. An unstable three dimensional KAM torus for the quintic NLS. https://arxiv.org/abs/1901.03512

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